diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index 95dd8607..23615fd6 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -19,6 +19,7 @@ Maxime "malavv" Lavigne
 Ripolak
 dafe
 presiyan
+Natureknight
 
 * DIABLO2 LOGO
 Jose Pardilla (th3-prophetman)
diff --git a/d2core/d2render/d2render.go b/d2core/d2render/d2render.go
index d0178a29..4cec0221 100644
--- a/d2core/d2render/d2render.go
+++ b/d2core/d2render/d2render.go
@@ -8,13 +8,17 @@ import (
 )
 
 var (
-	ErrWasInit         = errors.New("rendering system is already initialized")
-	ErrNotInit         = errors.New("rendering system has not been initialized")
+	// ErrWasInit holding an error instance for initialized rendering system
+	ErrWasInit = errors.New("rendering system is already initialized")
+	// ErrNotInit holding an error instance for non-initialized rendering system
+	ErrNotInit = errors.New("rendering system has not been initialized")
+	// ErrInvalidRenderer holding an error instance for invalid rendering system specification
 	ErrInvalidRenderer = errors.New("invalid rendering system specified")
 )
 
 var singleton d2interface.Renderer
 
+// Initialize the renderer
 func Initialize(rend d2interface.Renderer) error {
 	verifyNotInit()
 	singleton = rend
@@ -22,57 +26,68 @@ func Initialize(rend d2interface.Renderer) error {
 	return nil
 }
 
+// SetWindowIcon sets the window icon by a given file name as string
 func SetWindowIcon(fileName string) {
 	verifyWasInit()
 	singleton.SetWindowIcon(fileName)
 }
 
+// Run will run the renderer
 func Run(f func(d2interface.Surface) error, width, height int, title string) error {
 	verifyWasInit()
 	singleton.Run(f, width, height, title)
 	return nil
 }
 
+// IsDrawingSkipped checks whether the drawing is skipped
 func IsDrawingSkipped() bool {
 	verifyWasInit()
 	return singleton.IsDrawingSkipped()
 }
 
+// CreateSurface creates a new surface, which returns the newly created surface or error
 func CreateSurface(surface d2interface.Surface) (d2interface.Surface, error) {
 	verifyWasInit()
 	return singleton.CreateSurface(surface)
 }
 
+// NewSurface adds a new surface, and returns the new surface or error
 func NewSurface(width, height int, filter d2interface.Filter) (d2interface.Surface, error) {
 	verifyWasInit()
 	return singleton.NewSurface(width, height, filter)
 }
 
+// IsFullScreen checks whether the window is on full screen
 func IsFullScreen() bool {
 	verifyWasInit()
 	return singleton.IsFullScreen()
 }
 
+// SetFullScreen sets the window in fullscreen or windowed mode depending on the fullScreen flag
 func SetFullScreen(fullScreen bool) {
 	verifyWasInit()
 	singleton.SetFullScreen(fullScreen)
 }
 
+// SetVSyncEnabled sets or unsets the VSync depending on the given vsync parameter flag
 func SetVSyncEnabled(vsync bool) {
 	verifyWasInit()
 	singleton.SetVSyncEnabled(vsync)
 }
 
+// GetVSyncEnabled checks whether the VSync is enabled or not
 func GetVSyncEnabled() bool {
 	verifyWasInit()
 	return singleton.GetVSyncEnabled()
 }
 
+// GetCursorPos returns the exact current position of the cursor
 func GetCursorPos() (int, int) {
 	verifyWasInit()
 	return singleton.GetCursorPos()
 }
 
+// CurrentFPS returns the current frames per second
 func CurrentFPS() float64 {
 	verifyWasInit()
 	return singleton.CurrentFPS()
diff --git a/d2core/d2screen/d2screen.go b/d2core/d2screen/d2screen.go
index 65c26fb7..e43cdacf 100644
--- a/d2core/d2screen/d2screen.go
+++ b/d2core/d2screen/d2screen.go
@@ -10,8 +10,10 @@ import (
 	"github.com/OpenDiablo2/OpenDiablo2/d2core/d2ui"
 )
 
+// Screen is an exported interface
 type Screen interface{}
 
+// ScreenLoadHandler is an exported interface
 type ScreenLoadHandler interface {
 	// OnLoad performs all necessary loading to prepare a screen to be shown such as loading assets, placing and binding
 	// of ui elements, etc. This loading is done asynchronously. The provided channel will allow implementations to
@@ -19,14 +21,17 @@ type ScreenLoadHandler interface {
 	OnLoad(loading LoadingState)
 }
 
+// ScreenUnloadHandler is an exported interface
 type ScreenUnloadHandler interface {
 	OnUnload() error
 }
 
+// ScreenRenderHandler is an exported interface
 type ScreenRenderHandler interface {
 	Render(target d2interface.Surface) error
 }
 
+// ScreenAdvanceHandler is an exported interface
 type ScreenAdvanceHandler interface {
 	Advance(elapsed float64) error
 }
@@ -38,10 +43,12 @@ var singleton struct {
 	currentScreen Screen
 }
 
+// SetNextScreen is about to set a given screen as next
 func SetNextScreen(screen Screen) {
 	singleton.nextScreen = screen
 }
 
+// Advance updates the UI on every frame
 func Advance(elapsed float64) error {
 	switch {
 	case singleton.loadingScreen != nil:
@@ -97,6 +104,7 @@ func Advance(elapsed float64) error {
 	return nil
 }
 
+// Render renders the UI by a given surface
 func Render(surface d2interface.Surface) error {
 	if handler, ok := singleton.currentScreen.(ScreenRenderHandler); ok {
 		if err := handler.Render(surface); err != nil {
@@ -107,6 +115,7 @@ func Render(surface d2interface.Surface) error {
 	return nil
 }
 
+// LoadingState represents the loading state
 type LoadingState struct {
 	updates chan loadingUpdate
 }